A conventional spring mattress contains an elastic body and a filler, wherein the elastic body includes plural springs, a plurality of connecting wires, and plural fixing wires, wherein the plurality of connecting wires are applied to connect the plural springs to support a pressure as a user's turns his/her body, and the plural fixing wires are served to protect the plural springs. In addition, the filler is filled into a buffer layer between the user and the plural springs and is made of cloth and cotton or foam to obtain air permeation.
However, when the user gets up of off a bed, it is easy to fall off from the bed, because the conventional spring mattress has fixed elasticity.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.